1. Field of the Invention
The present invention relates to electromagnetic flow meters. More specifically, the present invention is directed to electrodes for electromagnetic flow meters.
1. Description of the Prior Art
The well-known electromagnetic flow meter is an instrument in which there is provided a magnetic field at a right angle through a fluid flow in a pipeline and also there are provided electrodes contacting the pipeline fluid for detecting flow quantity. The electrodes are located facing each other across the flow passing through said magnetic field and are intersecting the flow direction and the magnetic field at a right angle. The flow quantity can be determined by measuring an electromotive force that is generated between the electrodes in proportion to the average flow quantity. In the electromagnetic flow meter of this kind, the following prior art structure has been used in order to increase the level of the detected electromotive force between said electrodes without increasing the intensity of the magnetic field. Namely, according to the prior art structure, there are provided a plurality of pairs of rod type electrodes which are arranged along the wall of a fluid flowcarrying pipe so as to make a straight line along the axis of said pipe. Further, the electromotive forces generated between respective electrode pairs are summed to increase the total level of the electromotive force. According to the electrode arrangement like that, however, there occur the disadvantages that more pipeline sites are needed for installing the electrodes, that more pipeline area is required for installing the electrodes, that the size of the flow meter becomes larger, that the number of parts of the flow meter is increased, and so forth. Accordingly, it is desirable to provide an electrode structure for providing an increase in the detected flow signal while avoiding the aforesaid disadvantages of the prior art.